function getdivs(){
    var firstDiv=document.getElementsByClassName("introduce_banxin_top_left")[0];
    var secondDiv=firstDiv.getElementsByTagName("div");
    var thirdDiv=document.getElementsByClassName('introduce_banxin')[0];
    var fourthDiv=thirdDiv.getElementsByTagName("div");
    var com=document.querySelectorAll(".introduce_banxin_top_right>a")[3];
    secondDiv=Array.from(secondDiv);
    var arr=[secondDiv[0],secondDiv[3],secondDiv[6]];
    var div1=secondDiv[0].querySelector("div");
    var div2=secondDiv[3].querySelector("div");
    var div3=secondDiv[6].querySelector("div");
    fourthDiv=Array.from(fourthDiv);
    var arrs=[fourthDiv[12],fourthDiv[15],fourthDiv[46]];
    console.log(arr);
    console.log(arrs);
    console.log(com);
    for(let j=0;j<arr.length;j++){
        arr[j].onclick=function(){
            for(var i=0;i<arr.length;i++){
                arrs[i].classList.remove("appear");
            }
            arrs[j].classList.add("appear");
            com.innerHTML=this.querySelector("div").innerHTML;
        }
    }
}
getdivs();